Exhaust system question in Lounge as car is not an Oldsmobile . Car has an in line 6 with a single exhaust . Issue might be design of car , its a Fox body unibody . I am having an issue with heat transfer from the muffler to the inside floor of the car . The muffler has a heat shield built into the top of it , and at least an inch of air space between muffler and under side of car . Will stay with a single out from exhaust manifold , then maybe splitting off the exhaust Y to two mufflers. Would adding one more muffler / dual reduce down the temperature of the mufflers ? Or would they both be the same as what the single was . Has anyone gone from single to double and noticed the muffler temps drop ?